Method or process of manufacturing malleable-iron friction cylinders or shells for draft-gear.



` I J. F. OCONNOR;` METHOD `on Paoosss or MANUFAOTUBING MALLBABLB mon `Hno'rlon oYLINDBns on sHELLs ron DRAFT GRAB.

APPLIOATIOB FILED DBOZZB, 1810.

Patented Apr. 22, 1913.

i UNITED STATES PATENT OFFICE;

JOHN F. 0CONNOB,` OF CHICAGO,IILLINOIS, ASSIGNOR `T0 WILLIAM H. EINER, `0F

. CHICAGO, ILLINOIS;

METHOD 0R PROCESS OF MANUFACTURING MLLEABLE-IRON FRICTION CYLINDEBS OR SHELLS FOR DRAFT-GEAR Specification of Letters Patent.

Heretofore in the manufacture,ofmal-l leable iron friction shells or cylinders for friction draft gear, 1t has been customary after the white iron castings have been made and annealed in the usual manner packed in iron, steel or metallic chips :or scale, to finish and true up `by grinding lthe interior surface of the cylinder to correct such ir-` regularities or deviations from true cylin- -drical form` as ordinarily occur in ma ing causes; and also diiiiculty `sometimes from` malleable iron castings, and thus bring it to a true cylindrical shape `and give it a bright, metallic friction face or cylindrical surface. In practical use, hovvaver, difficulty is experienced with such malleable iron friction shells when combined lwith steel friction shoes" having hardened, smooth; friction faces from variation or lack of` uniformity in amount of frictional resistance developed under varying conditions of practical use, such, for example, as rusting of the ibright metallic friction face of the 'shell or other tendency to cut or to excessive Wear of the friction face of the cylinder when sliding against the friction shoes underthe enormously heavy pressure occasioned in practi` cal use of the draft rigging 1in cushioning bufling or pulling shocks of eavy trains.'

The object of my invention is to provide an improved process or' method of manu-i facturing malleable iron friction .shells by which the cost of manufacture `may be materially reduced and a much better product l when sliding against the hardened steel produced, one that will'be far` more durable than-those' heretofore in use, and which will develop a substantially uniform frictional resistance under different conditions of practical use or. service, and be entirely free from all liability to -cut or `unduly wear friction shoes under the heaviest pressure incident to bufling and pulling shocks of` trains. To practically accompllsh this important object or result, I clean from'sand, inishup and grind to the extent necessary to finishor smooth from sprues or protuberances, the hard, White iron casting `(from which the malleable iron friction cylinder or shell is to be formed) before, `it is, annealed; I then anneal' the cleaned and smoothed or finished hard, white iron cast-` y Patented Apr. 22, `1913A ingin a closed, sealed or muffled annealing` oven, without packing, enveloping or embracing the casting either `inside or outside in any iron or steel 'chips or scale or other packing, so that during the annealingprocess, air and gases havlng access to the cast-- lngthere will be produced on the castlng an: inner, external frictlon face layer or skin, to`

the depth or thickness of about one sixteenth of an inch, of relatively dense, relatively hard, relatively fine grained and short libered, and relatively brittle or friable metal a permanent exterior oxidized coating of a reddish` color, While the interior or body portion is relatively soft, relatively strong, relatively tough, relatively tenacious and relatively long fibered, and of the custom-` ary black `or dark -mallcable iron color; and then after the malleable iron shell `thus produced has been slowly cooled in the customary annealing way, it is, if out of true f cylindrical shape, subjected to internal pressure of an expansible shaping device to bring `its internal friction face to true cylindrical sha e or other shape required to properly `,an truly fit the friction shoes with which it is to coact, without grinding away, injuring `or removing the hard, dense friction face or Askin or the oxidized exterior or coating thereof with which it has been faces; of producing a substantially constant of a comparatively white color and having,`

provided in the annealing step of 1 my` I process.

amount of .frictional resistance under varying vconditions of practical use, that is to say, of maintaining a substantially constant coefficient; of friction; and of being ex.- tremely durable and 'entirely preventing land overcoming all tendency to cut or unduly be more full jected to theannealing step and indicating thejintegral friction lface layer'or skin of` relatively hard, tough, brittlemetal as compared with that `of the interior body -portion lof the malleable iron casting, 1n this view the 'friction shell lbeing represented as somewhat out of circular form in cross 'similar tol Fi V2, but showing' the friction' sha ed totrue circularformf without disvsection, as such castings may frequently be whenroriginally formed. Fig. 3 is a view `'shelli after-it as been, by internal pressure tur ing or removinganyportion of the friction Aface-layer "orskim Fig. 4 is al detail, enlarged; sectional view v of the finished cyi .lindrical friction shell. -Figq 5 is a longitudinal, diametrical section of, the friction shellvshowithe same with the shock abs Isorbing` mec anisn'r assembled therein, and taken substantially jon the line 5-5 of Fig.

16, andFig. 6 4is a transverse, sectional view, taken substantlally on the'line 6 6 of Fig. 5. Y In vthe 'drawing, 1 1 represents .i the. hard,

f white iron castin ,12fthe malleable iron friction `shell forme therefrom, 3 the friction face la er or skin on the innerv external surfaceo the shell and4 theoxidizedcoating;

'I54v 1re resents the; interior `soft,` strong,- ftough f odyj portion of the y1nallealflti iron v-In Figs.`5 and s, clairement 'frisson shoes, 7 the wedgeand anti-friction rollers i Y "which-f are interposed between the friction s hoesand wedge of the frictiondraft gear.

The friction shoes are'ipreferably of steel with case hardenedsmoothpolished friction A faces 9 and with case hardened wedgefaces 10 for 4engagement with the anti-,friction roller, which is preferablyof hardened tool steel, the wedge being preferably of cast steel with case hardened wedgefaces 11 for' I engagement with the anti-friction rollers.

As in my invention, the white iron casting V in the annealingstep in not embraced or enveloped byany packing material, the in.

ner fr1ction face layeror skin of theshell i especially `at vthe 'outermost portion thereo becomeshighly. oxidized'fto an appreciable depth and 1s thus rendered refractory and heat `resisting in character, and also of a character to eifectually resist any tendency f to weld, fuse or metallicallj,7 unite withthev bright metal of the friction shoes when slid- A in under enormously heavypressure.. This oxidized refractory outer portion of the friction face layer -of the shell thus e'ectuall prevents the interengaging faces of theshel and shoes from approachinglia, condition or state in which cutting, groovi'ngor excessivewear-can take place. A' Y I claim 1.? The method Vor v ing malleable iron friction draft gear shells consisting in first making a hard, white iron casting, then smoothing y or finishing the, same by removal of protuberanceathen; an-` nealing the same a d simultaneously providing the annealed shell withan interior friction'faeelayer p or skin of relatively hard, dense, brittlefand` friable -metal, `substantially as specied. -1

2. y The method or ing malleable iron friction draft gear shells consisting in first makingv a hard, white iron; casting, then y smoothing or `finishing y the I process `of manufacturprocess of' manufacturvsame by removal' of protuberances, thenanf j nealingl theA saine and simultaneously `providing p, the vannealed .shell with an interior friction layer lor, ,skin of relatively `hard,j1l)l) dense, brittle and` gfri'ablevmjetal, andfthen truing the4 shell .withoutfdisturbing-or re-f .Y movingsaid friction faee'layerorskn'by subj'e'ctnli` the malleablez'iro'n" shellto in -l ternal. a

.Spwifisd-` n Witnesses'i ping pressure, Ysubstantially j as JoHNf'F. ocoNNoR.. n 

